ALLEY EFFECT ON SEVERAL COTTON CULTIVARS IN SMALL PLOT RESEARCH

Abstract

Small plot research often necessitates the use of alleys or fallow areas along plot ends. To determine if there is an interaction between cotton (Gossypium hirsutum L.) cultivars of differing maturity group and the alley effect on plant yield, field studies were conducted in 1997 and 1998 in northeast Louisiana and south central Georgia. A randomized complete block arrangement of treatments was used with the cotton cultivars “Stoneville LA887” (STV LA887), “Delta Pine 5690” (DPL 5690), and “Paymaster 1215RR” (PM 1215RR). Plots were approximately 15 m long with 3 m alleys and were hand harvested in 0.3 m increments. Overall plot yield increased 12–15% by inclusion of lint from plants bordering the alleys. Lint yields were increased for the first 0.6 m from the alley. There was no interaction between cultivar and distance from the alley for yield although the change in boll number and boll size from the alley was not the same among cultivars. Plant height and number of main stem nodes was negatively correlated with distance from the alley across cultivars. Micronaire and fiber length were affected by cultivar, distance from the alley and their interaction. These results suggest that end trimming is not necessary for studies investigating cotton cultivars if lint yield is the only factor of interest. However, if fiber quality or yield components are of interest, plants within 0.6 m of the alley should be removed or not included for measurement.